I have received a couple of emails about Jappix MiniChat not working properly with Openfire BOSH. The main issue seems to be that the Openfire BOSH is not handling the reconnection properly as the user browses from page to page.
I'll be surprised if it did as the implementation was a few years ago and the BOSH specification has moved on since. More importantly was that it was designed to work with SparkWeb which was always resident on the web page until the user logged off. In this mode, Openfire BOSH works very well.
If this solution will work for you, then use the attached HTML file and adapt it to your needs.